Nitrogen-doped MnO₂nanorods as cathodes for high-energy Zn-MnO₂batteries

Abstract

The development of manganese dioxide (MnO[Formula: see text] as the cathode for aqueous Zn-MnO 2 batteries is hindered by poor capacity. Herein, we propose a high-capacity MnO 2 cathode constructed by engineering it with N-doping (N-MnO[Formula: see text] for a high-performance Zn-MnO 2 battery. Benefiting from N element doping, the conductivity of N-MnO 2 nanorods (NRs) electrode has been improved and the dissolution of the cathode during cycling can be relieved to some extent. The fabricated Zn-N-MnO 2 battery based on the N-MnO 2 cathode and a Zn foil anode presents an a real capacity of 0.31[Formula: see text]mAh[Formula: see text]cm[Formula: see text] at 2[Formula: see text]mA[Formula: see text]cm[Formula: see text], together with a remarkable energy density of 154.3[Formula: see text]Wh[Formula: see text]kg[Formula: see text] and a peak power density of 6914.7[Formula: see text]W[Formula: see text]kg[Formula: see text], substantially higher than most recently reported energy storage devices. The strategy of N doping can also bring intensive interest for other electrode materials for energy storage systems.